

public class Test1 {
    public static void main(String[] args) {
       StringBuilder strBud = new StringBuilder("abcdabcd") ;
//      strBud.delete(0,3) ;
//        System.out.println(strBud);
//        strBud.replace(0,1,"o");
//        System.out.println(strBud);
        strBud.reverse() ; 
        System.out.println(strBud);
    }
}
